Buff section for buffing wheels



,May 10, 1927.

R. E. HARRISON a: FOR BUFFING WHEELS BUFF SECTIO Filed Aug. 9. 1924 I IIPatented May it),

UNITED STATES ROBERT E. HARRISON, OF PHILADELPHIA, PENNSYLVANIA BUFFSECTIO1\T FOB BUFFING WHEELS.

Application filed August 9, 1924. Serial No. 731,011.

My invention relates to the construction of individual buff sectionssuch as are mounted upon shafts in varying numbers to form bufiingwheels.

One purpose is to arrange discs of fabric from the stubs of worn-outculling wheels in an annulus about a center with their in terlappinginner edges at a greater distance from the center than is required toreceive the butting wheel shaft and to fill. in the space between thediscs and the shaft by fabric inserts some of which inter-lap with thediscs.

A further purpose is to arrange discarded butting wheel discs in anannulus about the center spacing in the same layer by an arcapproximately equal to the radius to obtain regularity and balance ofusing the arbor holes in the discs as a spacing guide and at the sametime to avoid excessive thichening of the inner edge of the annulus byoverlapping.

A further purpose is to arrange overlapped annularly-placed sheets ofmaterial with reversing directions of the overlap in different layers.

A further purpose is to space annularly arranged overlapping sheets ofbuiiing material excessively from the center with respect to the supportintended and to balance and support them upon the shaft by centermaterial filled in along with the overlapped material and interlappedtherewith.

Further purposes will appear in the specification'and in the claims.

My invention relates to the buff sections themselves as well'as to themanner of construction of these sections.

I have preferred to illustrate my invention by a single form only,selecting a form which has proved to be practical, highly efficient andunusually economical and which at the same time well illustrates theprinciples involved.

Figure 1 is a side as partly constructed.

Figure 2 is an edge view of the structure seen in Figure 1.

Figure 3 is a side elevation similar to Figure 1 but showing thecompleted 'bu'lf section.

Figures t and 5 are side elevations of center filling members used.

A certain class of butiingwheels is made up of buff sections mountedalong and axially clamped about the shaft by which the elevation of asection wheels are to be rotated.

New sectionsfor such wheels are made up of full size sheets of newfabric.

When these butting wheels are worn down the supposedly worn out sectionshave generally been thrown away. A proposal has been made to use thestub discs of these sections in annular arrangement about a very smallopening intended to fit the buffing wh el shaft, but this structureproved unsatisfactory through the excessive overlapping of the innerportions of the discs about the small opening provided which made theinterior of the buff formed excessively thick as compared with the outerpart of it in dimensions parallel with the axis so that the properclamping of the buffs in the buffing wheel was prevented by excessivecompression of the inner portions of the buffs before the outer portionswere clamped. This construction further provided no reasonably ac curatemeans for distributing the stub discs about the annulus and no relief orcorrection for lack of proper balance with the result that the discswere apt to be irregular in distribution and the finished sectiondisplayed all of the vice of lack of balance which was inherent to theinitial annulus.

I have discovered that buff discs can be successively mounted in annulararrangement while obviating these objections if the discs be spaced fromthe center a greater distance than the size of the intended opening andthe center be filled in by center pieces interlapping sufficiently withthe inner edges of the buff discs to give this portion of the annulusapproximately the same thickness, and hence weight distribution forbalancing purposes as the rest of the annulus and at the same time tyingfast the center pieces with the rest of the buff. This makes the densityof the annulus substantially uniform throughout lts entlrety balancingit well throughout independently of the exact point selected for thecenter. I alsoprovide a firm supporting edge about the center opening.

The buff lap is thus balanced even if the center opening be not exactlyin the center of the circle of disc The outer edge is trimmedconcentrically with the inner opening.

In the formation of the buff section I lay the individual sheets 5 in anannulus so that their inner edges 6, define an opening larger than thenormal'arbor hole provided ill) for the shaft to which the butt section5 had previously been fitted.

In my care to avoid excessive overlap at the inner edges of the ring ofdiscs, I find it desirable not only to space the ring of discs from theintended inner opening but also to separate the individual discs whilein their overlapping progression to form a ring. For this latter purposeI find that their spacing from center to center is most desirablyapproximately equal to their radius. This affords me an easy andreliable guide for spacing their. so as to maintain good balance in thecompleted buff section by utilizing the arbor hole 7 in each discardedbuff disc as the to which or to a predetermined part of which the nextdisc is overlapped.

I find that I am able to secure better balance of the completed buffsections and avoid thick spots in them better by over lapping some ofthe layers in a clock rise direction and others in a counter clockwisedirection, securing the best results by reversing the direction of theprogression in adjoining layers. As a further means of protectionagainst unbalancing I mark my starting point for the first layer asalong some such radial line as 8 and then stagger my starting points forsuccessive layers by usii-lg a different line for each layer, spacedeach from the others, at least from the last, by a distance not amultiple of the spacing of mutually overlapping discs.

Whether the buff sections made from salvaged materials be made from newscraps or from discarded bull stubs the unequal thickness of thematerial used and the diiiiculty in securing proper balance of the buffsections as finished have proved real diiliculties.

The unequal thicknesses of parts of individual sections has not onlybeen objectionable in itself, because cun'iulative in the complete wheelbut it has frequently been oil center so as to unbalance the wheel andthus cause it to turn and buff unequally. Both of these objections areovercome by my invention.

It will be noted that the extreme inner edges 6 of the bull discs aslaid in each layer do not overlap and that there is a short distanceonly in my butt section where there is more than double the thickness ofthe disc material to a layer. As illustrated this takes place betweenthe points 9 and 110 but by slightly greater spacing can be avoidedaltogether if desired.

Within the opening I interleave section by section, core inserts 11 and12. The inserts 11 extend in between the inner edges of the discs of thesuccessive layers just far enough to be interleaved reliably with andthus fastened to the discs for support of the inserted core pieces bythe combined sired uniformity of thickness with care that there shall besufiicient interlapping of the core inserts and discs in theirentireties to give the support to the discs which their manner ofclamping into the finished wheel requires; also that the cross sectionin the central portion inside the annulus shall be of substantially thesame weight per unit as the cross section average through the sections.This can be secured by a little care and by using substantially circularor uniformly polygonal inserts.

The sections as thus formed preferably comprise overlapping discsarranged in annuli with an opening larger than the shaft, overlapping inalternate directions of laying and lilled in at the center with inserts,some of which interlap with the discs For these sections I providefacings 13 of material in one piece, a single piece or several piecessewed together, and sew the sections through these facings andpreferably along spiral lines shown at 1%. The sew ing should covernearly all of the radial depth as shown in Figure 2, if the main duty ofthe sections be cutting, or a part of the radial depth from the insideoutwardly, stopping at any desired point 15 if the intended duty bepolishing. The extent of sewing between these limits is de terminedlargely by the character of work intended to be done by the buff.

When the buff has been made up it will be noted that the arbor hole 16for the shaft may be out without the same requirement of care as to itscentering with respect to the ring of discs as would otherwise be:required because I have filled the interior opening within the bullswith material of uniform density and of approximately the same densityas the average density per unit i of the buff section throughout.

The outer edge at 17 is trimmed to a circle concentric with the arborhole 16 for the shaft, thus producing a well balanced thoroughly unitedsection of uniform thickness.

It will be evident that the same advantage pointed out in regard to theconstruction of my butt sections would be present though of less degree,if the annular layers of discarded butl' discs be interspersed withlayers ill) loo

If U

are impregnated with the lubricating and,

abrasive materials which have been applied to the butting wheel duringthe bulling oper ations and my invention is of special value in makingmore practical the use of this desirable material. Moreover theoverlapping butl' discs present a rapid succession of changes ofdirection of fibres in the fabric used. presenting a greatly increasednumber of corners of firm material free from ravelling as compared withnew fabric discs extending each completely to the circumference. Thematerial of the discarded buff discs is thus both cheaper and betteradapted to butting than new material would be.

It will be obvious that in view of my disclosure modifications andchanges will occur to others skilled in the art, which secure a part ofthe invention by similar though not identical means and it is my purposeto include herein all such modifications and changes as come within thereasonable spirit and scope of my claims.

Having thus described my invention, what I claim as new and desire tosecure by Letters Patent is:

1. A butt section adapted to be mounted upon a buffing wheel shaft, andcomprising a plurality of uniformly arranged overlapping discs inannular arrangement spaced across the center of the annulus by adistance considerably greater than the diameter of the shaft to preventbunching of the overlapping close to the shaft and filling material forthe space about the shaft, some of which overlaps the inner edges of thediscs.

2. In a buiiing section adapted to be mounted upon a bufiing wheelshaft, the combination of a plurality of discs from discarded bufiingwheel stubs annularly arranged to overlap about a central opening largerthan the shaft and having some of the layers overlapping in oppositedirections from other layers, in combination with a fabric filling forthe opening about the shaft firmly secured to the interior of theannular layers of discs.

The method of building up a butt section from the discarded discs ofbufl' stubs which consists in placing the discs in overlapping'relationto form annuli spaced at the inner edges of the discs across the centerto a considerably larger diameter than that of the shaft to preventbunching of the overlapping of the discs close to the shaft and fillingin the center with fabric material in part at least interlapping withthe inner edges of the discs.

4. The method of building up a buff section from the discarded discs ofbufi stubs which consists in placing the discs in overlapping relationto form annuli spaced at the inner edges of the discs across the centerto a larger diameter than that of the shaft, forming successive annuliof discs overlapping in opposite directions, and filling in the centerwith fabric material interlapping with the edges of the discs.

ROBERT E. HARRISON.

